Potential mayoral candidates Council Speaker Gifford Miller and City Comptroller William Thompson would have their fund-raising efforts severely hamstrung if Mayor Bloomberg’s proposal to limit contributions from companies that have business with the city is enacted.

For the 2005 race for City Hall, both the council speaker and city comptroller already have reaped tens of thousands of dollars from individuals employed by businesses and lobbyists that have dealings with the city.

Miller has accepted donations from a range of people working for companies and organizations that are financially tied to the city including lobbying firms, taxi operators and museums.

A spot check of campaign-finance reports reveals that four employees from Eshel Management – a company involved in the city’s scatter-site shelter program – combined to give the speaker more than $10,000.

Employees of at least three companies that have contracts with the city have each given Thompson the maximum under the city’s campaign-finance law – $4,950 – for his as-yet-undeclared 2005 race.

As it stands today, candidates running for mayor are allowed to accept up to the maximum $4,950 from any individual, but only up to $250 of those contributions is eligible for the Campaign Finance Board’s 4-to-1 public matching-funds program.

Under Bloomberg’s proposal, employees of companies having business with the city would be limited to giving a maximum of $250, and those funds would not be matchable.